The organic object which includes excitable cells such as neurons or cardiomyocytes can generate action potentials. Under physiologic condition, cellular membrane potential is induced through ion permeability between the inner and the outer sides of the membrane in excitable cells. The excitable cells are responsible for cell-cell communication and triggering action potential.
Electrophysiology is a study that investigates the electrical properties in living cells and tissues while cardioelectrophysiology is the study focusing on cardiomyocytes or cardiac tissues.
Cardioelectrophysiology is a major index for studying the cardiac function and cardiac pathology. Optical image mapping system is one of powerful tools for analyzing cardioelectrophysiology; however, conventional optical image mapping systems still have remaining drawbacks and need to be solved.
Conventional optical image mapping system 1 illustrated in FIG. 1 mainly comprises an optical instrument 11 for inspecting cardiac tissues or organic objects 10 disposed on a platform 13, and an image acquiring unit 12. The optical instrument 11 further comprises a light source 110, a collimating lens 111, a beam splitter 112, a filter 113, and lens 114. In the optical image mapping system 1, the cellular membrane potential can be altered during variation period of action potential, so the chemical resonant structures of the voltage-sensitive dye is changed accordingly. The excition fluorescence generated by the voltage-sensitive dye will be transformed to the image acquiring unit.
The fluorescent light signals are amplified by the optical instrument 11 and recorded by the image acquiring unit 12 such as charge-coupled device (CCD). The optical image mapping system 1 for assisting the research of cardioelectrophysiology is irreplaceable due to merits of (1) collecting variation of cellular membrane potential signals by an optical scanning without contacting the tissue; (2) providing superior spatial and temporal resolution of action potential signals than obtained by the array electrodes inspection; (3) preventing the electrical noise interference in the recorded electrical signals. Despite of the merits described above, however, the conventional optical image mapping system requires image acquiring unit having high speed camera and massive image files storage media, so the cost of the system is going expensive. Meanwhile, the limits of required inspection time and image resolution are also the causes that the optical image mapping system can't be commonly applied in the field of electrophysiology.
In addition, conventional arts like US. Pub. No. 2008/0188727 disclosed an improved spectroscopy illuminator for generating broadband light and for delivering the light to a sample with an improved delivery efficiency, for higher optical density and/or reduced thermal transfer uses a solid-state broadband white LED to produce broadband light, which is then transmitted to a sample region, such as a living tissue or blood in vivo or a biological sample in a spectrophotometer target region. The solid-state source keeps both the illuminator and sample cool during operation, allowing the illuminator to be integrated into the tip of a medical probe, a medical system such as an oximeter, or other monitoring systems or devices making measurements based on light scattering, absorbance, fluorescence, phosphorescence, Raman effects, use of a contrast agent, or other known spectroscopy techniques.
Besides, U.S. Pat. No. 6,680,780 also discloses a method and system to actively stabilize a probe mounted on a manipulator such that the probe moveable in response to a control voltage. A laser interferometer is utilized to transmit a first light beam to the subject and to receive a reflected light beam, to modulate a second light beam with a radio frequency signal to form a reference light beam, and to combine the reflected light beam and the reference beam to form an interference pattern. A demodulator is utilized to demodulate a phase shift of a radio frequency component of the interference pattern to determine a displacement signal representative of an amount and direction of subject movement, and to convert the displacement signal to the control voltage. The probe is then moved in response to the control voltage, providing stabilization relative to subject movement, and the probe may then be utilized for desired measurements within the subject.